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Background Cereals and cereal-based products as an important part of the daily diet provide a considerable percent of macronutrients such as carbohydrate, protein and fiber and a range of micronutrients including vitamins (E and some of the B vitamins) and minerals (Mg and Zn). However, thermal (boiling or baking) and mechanical (milling) processes applied for conversion of cereals into consumable products and also improvement of the digestibility and palatability of cereal products lead to the reduction or even removal of some bioactive compounds, consequently loss of their nutritional and health values. Scope and approach The fortification process is a suitable means for the addition of the lost components to the formulation of cereals; although, direct usage of bioactive compounds and additives in bakery products has some limitations such as sensitivity to undesirable environmental and processing conditions, adverse effects on sensory attributes of products and interaction with other food ingredients. Encapsulation not only can solve these problems, but also improves the overall quality and shelf life of bakery products by release controlling, protecting and uniform distribution of these components. Key findings and conclusions Most studies in the literature show that the use of bioactive substances instead of free compounds can be used effectively to enrich or fortify cereal-based products, without having a significant negative impact on their physicochemical and textural properties. Spray drying was the most commonly used technique for encapsulation of bioactive compounds, which can be explained by its advantages such as flexibility and low cost. This review will provide valuable information that may be useful for identifying trends in the production of new functional cereal-based products through nano/microencapsulation technology. However, it is necessary to pay attention to the commercialization and also the safety of nanoformulations used in cereal products.

This work develops an all-electrical, reliable, rapid antibiotic susceptibility testing device to monitor antibiotic efficacy in bacterial biofilms that can be practically translatable to clinical settings and industrial antibiotic developments.

Accurate phasor estimation under various faulty conditions is one of the most critical issues in the monitoring, protecting, and controlling of a microgrid (MG). This paper presents a new phasor estimation algorithm (PEA) under fault conditions for MG applications. The main features of this method are to accurately phasor estimation of the signal combination of a decaying dc offset, a decaying fundamental frequency component, and harmonics. In this strategy, a Taylor series is replaced by the exponential functions of the fundament frequency and decaying dc offset component. Then, the time constants and the magnitudes of decaying components are estimated by the least square method. The proposed method is explained theoretically, and its performance is demonstrated by simulating various numerical signals in MATLAB and measured signals during fault conditions. The simulation results indicate that the proposed method estimates the dynamic phasor during fault conditions, accurately. Furthermore, a comprehensive comparison with the conventional methods is carried out to show the effectiveness of the proposed algorithm.

In this study, a hybrid material was successfully fabricated through the hybridization of zinc-based metal–organic framework (Zn-MOF) and covalent organic framework (COF) based on melamine and terephthaldehyde (Zn-MOF/COF) and characterized by FT-IR, SEM, XRD, and STA analysis. Then, the resultant hybrid was employed as an amazing and cost-effective catalyst in the condensation of a variety of aldehydes with malononitrile under solvent-free conditions at 25 °C in a short time (5–60 min) to offer benzylidenemalononitrile derivatives in high yields (82–100%). The catalyst could be reused without a noteworthy drop in catalytic activity at least eight times. The use of Zn-MOF/COF catalyst outcomes under mild reaction conditions in very short reaction time, exceptional catalytic activity, high recyclability and an easy work-up process for the Knoevenagel condensation.

Metal-oxide based gas sensors are widely used as the gas sensing elements in industrial and residential areas. Many efforts have been made to increase sensitivity and reduce the working temperature of metal-oxide based gas sensors. In this paper, ZnO nanowires (NWs) were successfully grown on graphene (Gr) nanosheets by the hydrothermal method. The synthesized Gr/ZnO NWs nanocomposite were investigated as the sensing material. Not only is the sensor response much higher, it also works in a lower working temperature toward a low concentration of ethanol in comparison with pure ZnO NWs. The optimum working temperature is reduced from 200 °C in pure ZnO NWs to 125 in Gr/ZnO NWs sensor. The maximum response of the Gr/ZnO NWs sensor is 26, which is approximately enhanced twice as much as the pure ZnO NWs sensor. The lower limit of detection (LLOD) of the proposed sensor is as low as 1 ppm ethanol vapor. The sensor was shown a high response, good selectivity, fast response toward ethanol vapor, excellent repeatability, and low sensitivity toward a high relative humidity, as well as remarkable long-term stability.

Pseudomonas aeruginosa is the most important opportunistic pathogen leading to serious and life-threatening infections, especially in immunocompromised patients. Because of its remarkable capacity to resist antibiotics, the selection of the right antibiotics with the exact dose for the appropriate duration is critical to effectively treat the infections and prevent antibiotic resistance. Although conventional genotypic and phenotypic antibiotic susceptibility testing (AST) methods have been dramatically advanced, they have suffered from many technical and operational issues as a generalized antibiotic stewardship program. Furthermore, given that most microbial infections are caused by their biofilms, the existing AST methods do not provide evidence-based antibiotic prescribing guidance for biofilm-based infections because the results are based on individual bacteria traditionally grown in their planktonic form. In this work, we create an innovative susceptibility testing technique for P. aeruginosa that offers clinically relevant guidelines and widely adaptable stewardship to effectively treat the infections and minimize antibiotic resistance. Our approach evaluates the antibiotic efficacy by continuously monitoring the accumulated electrical outputs from the bacterial extracellular electron transfer (EET) process in the presence of antibiotics. Our innovative paper-based culturing 3-D scaffold promotes surface-associated growth of bacterial colonies and biofilms. The platform replicates a natural habitat for P. aeruginosa where it can grow similarly to sites it infects. Our technique enables an all-electrical, real-time, easy-to-use, portable AST that can be easily translatable to clinical settings. The entire procedure takes 96 min to provide evidence-based antimicrobial prescribing guidance for biofilm-based infections.

In this research, an aqueous reflux method was utilized to synthesize copper sulfide nanostructures with different morphologies, such as flower-like based nanosheets and spherical nanoparticles. The reaction was performed in oleic acid medium, using copper(II) acetylacetonate [Cu(acac)2] and elemental sulfur as the Cu2+ and S2− sources, respectively. Then, the effect of refluxing temperature, precursor molar ratios and reaction time on the particle phase and morphology of synthesized particles was investigated. The results show that a 1 : 1 ratio of [Cu (acac)2] to S2− at 200 °C reflux temperature for 10 h exhibit optimum conditions for forming a pure hexagonal Cu7.2S4 phase. Then, the surface of the synthesized Cu7.2S4 was also modified by hydrophilic polyethylene glycol (PEG), and the modified nanoparticles were used in the release of the drug doxorubicin at pH = 5.4, pH = 7.4 under in vitro conditions, which was monitored by UV-Vis spectroscopy. The results showed that drug release under acidic conditions is greater than that under neutral conditions. Furthermore, by increasing the sulfur content, the sample's morphology was changed from a spherical shape to flower-liked based nanosheets, and the phase tends to be the CuS phase. Finally, the synthesized Cu7.2S4 nanostructures were used for the photocatalytic degradation of some dyes, including Reactive Blue 21 (RB21), Reactive Red 120 (RR120), and Reactive Orange 5 (RO5). The results showed that the highest degradation percentage for RB21 pigment was 99%.

The fabrication of magnetic porous nanocomposites is of great significance owing to their excellent properties and their application as promising catalysts. Herein, a novel covalent organic framework (COF)-modified magnetic chitosan (CS) supported copper (Fe3O4/CS/COF/Cu) nanocomposite was prepared through modification of Fe3O4 with CS, chemical attachment of melamine-rich COF on Fe3O4/CS followed by reaction with Cu(NO3)2·3H2O. The resulting nanocomposite was characterized by FT-IR, XRD, SEM, TEM, EDX, BET and VSM analyses. Fe3O4/CS/COF/Cu possesses large specific surface area and supermagnetism, making it an ideal catalyst for the organic reactions. Thus, Fe3O4/CS/COF/Cu was applied as an efficient and recoverable catalyst for the green and rapid synthesis of biologically active polyhydroquinoline derivatives via the unsymmetric Hantzsch reaction under solvent-free conditions. Fe3O4/CS/COF/Cu exhibits high reactivity and selectivity for the preparation of different derivatives of polyhydroquinolines under mild reaction conditions and short time. Furthermore, the catalyst was recovered and reused several times without an important decrease in efficiency.

A novel mesoporous composite was prepared through the hybridization of cobalt-based metal-organic framework (Co-MOF) and covalent organic framework (COF) based on melamine and terephthaldehyde (Co-MOF/COF) and characterized by FT-IR, SEM, XRD, EDS, BET, and STA analyses. The resultant composite was utilized as a robust recoverable catalyst in the condensation of several aldehydes with malononitrile to produce benzylidenemalononitrile derivatives in 62–94% yields under solvent-free conditions at room temperature using 15 mg of the catalyst and 5–60 min of reaction. The examination of catalytic performance of designated Co-MOF/COF exhibited an outstanding activity for the Knoevenagel condensation in a very short time. The recoverability, reusability and durability of Co-MOF/COF have also been investigated under applied conditions.

A new adsorbent, poly(amide-imide)/zinc sulfide nanocomposite (PAI/ZnS NC), was fabricated and identified by Fourier-transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, field emission-scanning electron microscopy, and transmission electron microscopy. Then, the obtained NC was applied for the simultaneous removal of auramine O (AO) and rhodamine B (RB) dyes from aqueous solution via the interactions of hydrogen bonding, π– π stacking, and Lewis acid–base interaction. The effects of operational variables including pH, PAI/ZnS NC mass, AO and RB concentration, and sonication time on removal efficiency were examined and optimized values were found to be 8.0, 16 mg, 11 mg L−1, and 6 min, respectively. The adsorption capacities of PAI/ZnS NC for the removal of AO and RB dyes were found to be 70.92 and 91.74 mg g−1, respectively. Ultraviolet–visible spectrophotometer was used to determine the amount of residual dye in solution. Fitting the experimental equilibrium data to isotherm models such as Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich reveals the suitability of the Langmuir model with high correlation coefficients ( R2 = 0.998 for AO and R2 = 0.999 for RB). Pseudo-first-order, pseudo-second-order, intraparticle diffusion, and Elovich kinetic models applicability was tested and the pseudo-second-order equation controls the kinetics of the adsorption process. Furthermore, this study establishes that PAI/ZnS NC can be successfully applied as a low-cost adsorbent and conserve its high efficiency after nine cycles for the removal of AO and RB dyes.

Background Decision making regarding the treatment of neonates with poor prognoses is difficult for healthcare staff working in the neonatal intensive care unit (NICU). This study aimed to investigate the attitudes of physicians and nurses about the value of life and ethical decision making when encountering neonates with poor prognosis in the NICU. Methods This cross-sectional study was conducted in five NICUs of five hospitals in Tehran city, Iran. The attitudes of 144 pediatricians, gynecologists and nurses were assessed using the questionnaire of attitude toward the value of life and agreement on intensive care management based on three hypothetical case scenarios of neonates with poor prognosis. Data were analyzed using descriptive and inferential statistics via the SPSS software. Results The negative agreement on the no initiation of intensive care measures and the discontinuation of resuscitation in neonates with poor prognosis was more than the positive agreement. Also, various factors influenced the participants’ decision making for the provision of care to neonates. Regarding the case scenarios, the participants agreed on the provision of aggressive, conservative, and palliative care with various frequencies. This study confirms the importance of healthcare providers’ perspectives and their impacts on ethical decision making. The participants favored the value or sacredness of life and agreed on the use of all therapeutic measures for saving the lives of neonates with poor prognosis. Conclusion More studies are required to improve our understandings of factors influencing ethical decision making by healthcare providers when encountering neonates with poor prognosis in NICUs.

The objective of this paper was to select the best infectious waste treatment alternative by Sustainability Assessment of Technologies (SAT) methodology. This study was carried in four educational hospitals of Ardabil University of Medical Sciences. The average waste produced in hospitals was 4.7 kg/bed/day. The average of common waste, infectious waste, sharp waste, and chemical and pharmaceutical waste was 2.18, 2.42, 0.04, and 0.05 kg/bed/day, respectively. In detailed assessment, a weighted sum matrix method was used to rank the different technologies of infectious wastes treatment. Finally, the highest score was found for Autoclave with a shredder (64.53), and hydroclave (63.32), autoclave (60.61), central incineration (55.12) and chemical treatment (54.25) were ranked second to fifth, respectively. Most participants emphasized the need for an autoclave with a shredder in the treatment of infectious hospital waste in Ardabil. However, the environmental and economic criteria and other aspects of treatment infectious hospital waste should be considered.

A tetramine monomer containing porphyrin moiety is prepared in high purity by the propionic acid-mediated condensation of pyrrole with 4-cyanobenzaldehyde and then reduction in the tetracyano intermediate. The thermally stable porphyrin-based polyimides (PI)s are prepared using tetramine and four aromatic tetracarboxylic dianhydrides via a two-step method in quantitative yields with inherent viscosities of 0.34–0.63 dL/g. The PIs are soluble in some organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide and dimethyl sulfoxide. The resultant PIs had high glass transition temperatures and displayed outstanding thermal stability up to 500 °C. The resulting polymers revealed strong UV–Vis absorption band around 422 nm in DMF. Wide-angle XRD measurements exhibited that the PIs were amorphous. The polymer films had tensile strengths 101–128 MPa, elongates at break of 7–11% and tensile moduli of 2.0–2.2 GPa. One of the PIs was applied to examine the adsorption properties of two heavy metal ions (Cd2+ and Hg2+) at pH 7. The results revealed that the applied PI was an outstanding sorbent for heavy metal ions. The goal of this study is the preparation of hydrophobic PIs for ion-selective membranes and chemical sensors to adsorb of toxic heavy metals.

The paper presents the transient behavior of the doubly fed induction generator (DFIG) in the wind turbine (WT) in the normal and voltage dip condition. When voltage dip occurs in to the grid, the rotor current increases and the DC-link voltage increases too and start to oscilate. In this paper, the proportional integral (PI) controllers are used to control the DFIG-basedwind farms for regulating the electronic devices including rotor side converter (RSC) and grid side converter (GSC) to control the active and reactive power of DFIG. The PI parameters are tuned by imperialist competitive algorithm (ICA). So, the transient behavour of the DFIG-based WF is explors when the voltage dip occurs. Hence, the induced electric motive force in to the rotor is measured. Also, an existed uncertainty for mutual inductance is considered caused by saturated curve during three-phase fault conditions and the bahavour of DFIG-based WT is examined and analyzed. All of simulation is done by Matlab/Simulink®.

Background: Shivering frequently occurs in cesarean section (CS) under spinal anesthesia (SA), resulting in several complications. To date, pethidine has been considered as the gold standard for post-SA shivering control, but it is contraindicated in breastfeeding women. Methods: This randomized, double-blind study was conducted at Alzahra hospital in Guilan, Iran, From January 2019 to November 2020. A total of 508 eligible term parturient women were enrolled and randomly divided into four groups of low dose ketamine (K), tramadol (T), ondansetron (O), and placebo (P). The incidence and severity of shivering and patients’ complications were recorded and compared among the groups. Results: The patients were homogenous in terms of demographic variables. Shivering was witnessed in 68 (53.5%), 26 (20.5%), 75 (59.1%), and 82 (64.6%) patients in K, T, O, and P groups, respectively (P = 0.0001). Regarding shivering severity, there was a significant difference among the four groups (P = 0.0001). In addition, a significant difference was seen regarding Apgar scores at the first minute, but not at the fifth minute (P = 0.168). Conclusions: Considering the high incidence of shivering in placebo group, prophylactic intervention in CS under SA seems to be necessary. Among the studied drugs, tramadol was the most effective one, followed by a low dose of ketamine and ondansetron.

The present study focused on utilizing the advantages of porous covalent organic frameworks by preparing them in a usable magnetite support form with Fe3O4 nanoparticles using the solvothermal meth...

The ternary superparamagnetic nanocomposites consisting of graphene oxide (GO), Fe3O4 nanoparticles, and optically active poly(amide-imide) (PAI) were fabricated in three steps consisting of a facile one-pot in situ growth of Fe3O4 on GO, resulted in the preparation of the magnetic Fe3O4@GO, modification of Fe3O4@GO by 3-aminopropyltriethoxy silane to introduce amino groups on its surface, and subsequently its compositing by various levels of 5, 10, and 15 wt% with chiral PAI derived from 3,5-diamino- N-(4-(di(1H-indol-3-yl)methyl)phenyl)benzamide and N, N′-(4,4′-carbonyldiphthaloyl)-bis-l-phenylalanine diacid through ultrasonic irradiation. Characterization of the resulting nanocomposites was performed by Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, scanning electron microscope (SEM), and thermogravimetric analysis (TGA). The SEM analysis showed Fe3O4 nanoparticles with 30 nm size successfully decorated the GO nanosheets. The TGA analysis established the expected thermal stabilities for PAI/Fe3O4@GO nanocomposites. Furthermore, incorporation of Fe3O4@GO in polymer matrix improved the mechanical properties substantially. PAI/Fe3O4@GO 10 wt% was used to evaluate the sorption properties of Hg2+ at pH 7.

Two novel optically active poly(amide-imide)s (PAI)s were prepared by the direct polycondensation of diamine, 3,5-diamino-N-(4-(5-(4,5-diphenyl-1H-imidazol-2-yl)furan-2-yl)phenyl)benzamide with two optically active dicarboxylic acids such as N,N′-(pyromellitoyl)-bis-l-phenylalanine and N,N′-(4,4′-carbonyldiphthaloyl)-bis-l-phenylalanine in molten tetrabutylammonium bromide (TBAB) as a green medium with triphenyl phosphite as condensing agent. The diamine was synthesized via the direct condensation of 2-[5-(4-aminophenyl)furan-2-yl]-4,5-diphenyl-1H-imidazole with 3,5-dinitrobenzoyl chloride and following reduction in the dinitro compound. The resulting PAIs had inherent viscosities of 0.38 and 0.35 dL g−1. The PAIs were dissolved in polar organic solvents, such as NMP, DMAc, DMSO and DMF at room temperature. These polymers were solution-cast from DMAc solution into transparent, flexible and tough films. Wide-angle X-ray measurement exhibited that the PAIs were amorphous. These PAIs had 10% weight loss temperatures of 427 and 440 °C under nitrogen atmosphere. The polymer films had a tensile strength of 102 and 108 MPa and a tensile modulus of 2.2 and 2.3 GPa. The adsorption capability of one of the PAIs for removal Cu2+ from aqueous solutions was tested at pH 5.

Polyimide (PI)/Fe3O4 nanocomposites were successfully prepared via the thermal curing of different amounts of Fe3O4 nanoparticles (2, 4, 6 and 8 wt%) functionalized by 3-aminopropyltriethoxy silane as a coupling agent, containing the poly(amic acid) derived from 5-diamino- N-(4-(4,5-diphenyl-1H-imidazol)phenyl)benzamide and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride. The effect of Fe3O4 nanoparticles on the structural, thermal and magnetic properties of nanocomposites was investigated. The Fourier transform infrared spectroscopy and scanning electron microscopy (SEM) results reveal that the surface of Fe3O4 nanoparticles is sufficiently compatible with PI through linkage of the coupling agent between Fe3O4 and the polymer. Also, the SEM image shows that Fe3O4 nanoparticles are dispersed uniformly in the polymer matrix, with a particle size of around 78 nm. The nanocomposites of 2 and 8 wt% exhibit the saturation magnetization values of 0.055 and 0.170 emu g− 1, respectively. The thermogravimetric analysis data show that the thermal stability of the nanocomposites is improved as compared to the pure PI.

The exploration of magnetic polymer nanocomposites is of great importance owing to their unique properties and promising applications. Herein, for the first time, the ternary superparamagnetic nanocomposites of Fe3O4 nanoparticles, graphene oxide (GO) and optically active poly(amide–imide) (Fe3O4@GO/PAI) were prepared and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, scanning electron microscope (SEM) and thermogravimetric analysis (TGA). The preparation was attained via a three-stage process consisting of a facile one-pot in situ growth of Fe3O4 on GO, resulted in the preparation of the magnetic Fe3O4@GO, modification of Fe3O4@GO by 3-aminopropyltriethoxy silane to introduce amino groups on its surface and subsequently its compositing by various levels of 4.0, 6.0, 8.0, and 10.0 wt% with chiral PAI through ultrasonic irradiation afforded the magnetic nanocomposites (NanoFe3O4@GO/PAI). The SEM analysis showed Fe3O4 nanoparticles with 30 nm size were successfully decorated the GO nanosheets. The TGA analysis established the expected thermal stability for Fe3O4@GO/PAI nanocomposites. Furthermore, incorporation of Fe3O4@GO in polymer matrix improved the mechanical properties substantially.

Background Curcumin, the major bioactive material of turmeric, has wide functional features such as anti-diabetic, anti-cancer, anti-inflammatory, and antioxidant activities. However, curcumin exhibits some major limitations including low water solubility, degradation during processing or within the gastrointestinal tract and alkaline conditions, leading to decrease of its bioavailability. For these reasons, many studies have tried to improve functionality of curcumin and overcome its limitations through delivery systems, especially nanoencapsulation. Scope and approach In this review, practical applications of the nanoencapsulated curcumin, prepared by various techniques in different food, pharmaceutical and cosmetic products have been considered and explained. The importance of nanoencapsulation in improving functional effects of curcumin in processed foods, such as coloring, antioxidant and antimicrobial activity has been discussed thoroughly and its potential applications for medicinal proposes including cancer, cardiovascular and neurodegenerative diseases, viral and bacterial infections have been reviewed. Key findings and conclusions Nano-delivery systems, because of exclusive characteristics of nanoparticles as well as conventional properties of an encapsulation medium, can provide chemical stability, hydrophilicity, sustained release and adequate dispersibility of curcumin in final products (food, cosmetics and drug). Consequently, the pharmacokinetic properties of curcumin including biological half-life and bioavailability (or bioaccessibility) can be improved resulting in better clinical and functional efficacy in vivo. Although the potentials of curcumin nanoformulations have been extensively studied in the literature, future studies can better help to find optimum formulations for clinical and industrial applications of nanoencapsulated curcumin.

A new diamine monomer containing indole unit, 3,5-diamino- N-(4-(di(1H-indol-3-yl)methyl)phenyl)benzamide, was successfully synthesized and applied in the preparation of a series of polyimides (PIs) via a conventional two-step polymerization procedure with three aromatic tetracarboxylic dianhydrides. The prepared polymers showed excellent solubility in organic solvents such as N-methyl-2-pyrrolidinone (NMP), N, N-dimethylacetamide, and N, N-dimethylformamide. Flexible and strong films of PIs were obtained via casting from their solutions. The glass transition temperature of these polymers was in the range of 223–264°C. They were fairly stable up to a temperature around 300°C and lost 10% weight at 372°C in nitrogen atmosphere. All of the polymers revealed absorption maxima around 323 nm with a fluorescence emission maxima around 378–406 nm in NMP. The cyclic voltammetry of the PIs exhibited an oxidation wave with a peak at 1.07 V. The resulting polymer films had tensile strengths from 83 MPa to 107 MPa, elongates at break of 7–10%, and tensile moduli of 2.2–2.3 GPa.

In recent decades, due to the increase in awareness, most consumers prefer foods that not only satisfy their primal urge of hunger but also include health-promoting effects on the body. Therefore, the food industry has an increasing tendency to apply the nutrients (like vitamins, essential fatty acids and minerals) and replace synthetic additives with natural bioactives (like phenolics and essential oils) to produce functional products. However, low dispersibility and shelf-stability as well as presenting unpleasant taste and odor are the most critical barriers for direct incorporation of these useful compounds into foods. In this context, nanoencapsulation has been proposed as a relatively new solution to overcome the mentioned limitations. However, fewer studies have focused on incorporating the bioactive-loaded nanocarriers into the food matrices. This study intends to help the development of functional food production by doing an exhaustive review on the incorporation of nanoencapsulated ingredients into the real food system and resulted interaction of nanocarriers and food products. According to the literature, incorporation of the nanoencapsulated bioactive ingredients into foods can be effectively used to enhance their stability during the processing and storage stage and their bioavailability as well as to delay lipid oxidation and microbial growth in food, without negatively affecting physicochemical, organoleptic and qualitative properties. However, some published results to date declared that food matrix might adversely affect the bioavailability and antimicrobial activity of nanoencapsulated ingredients. It seems that further studies are required to contribute to the choice of appropriate healthy ingredients and wall materials for incorporating into a given food structure.